Quota FTP

I have problem with quota size on pure-ftpd, debian 5 lenny, ISPConfig 3.0.1.
Set the Quota for website 100MB then customer adding ftp account with 1GB quota why ?
Next problem is customer create ftp account with 1MB quota the connecting to ftp like this account and uploading 2MB files why? if this user have only 1MB quota ?

Best Regards

EDIT:

Ok i resolve problem with reading quota size by pure-ftpd.
I still do not know why the customer can create account with ftp quota greater than the quota for the website

Solution to the problem of quota in the pure-ftpd:
I comment this line and change option from quota_files != '-1' to quota_files = '-1' in mysql.conf and limits for ftp session is now ok.